Polishing-machine.



H. J. WEBB.

POLISHING MACHINE. APPLICATION.FILED JULY 13. 1914.

1 QLQQ QQQQ Patented May 25, 1915.

HARRY a. WEBB,

F DETROIT, MICHIGAN.

EOLISHTNG-MACHINE.

ma tea,

Specification of Letters Eatent.

Patented May 25, 11915.

Application filed July 13, 191 Serial No. $50,538.

To all whom it may concern Be it known that T, HARRY J, WEBB, a

citizen of the United States of America, re-- surface to be polished and a continuous motion thereof transversely of the plane of a longitudinal axial rotation of the work With these and other ends in View, the invention consists in providing a flexible bufiing or polishing member and a forming member therefor to cause said bufiing memher to assume a shape in conformity to the curvature of the surface of the work, and further, in the matters hereinafter more fully set forth, all as pointed out in the appended claims, reference being had to the accompanying drawing in which- Figure 1 is a side elevation of a machine embodying the invention; Fig. 2 a plan view of the same; Fig. 3, is a sectional detail of a guide and bearingnhain; Fig. 4. is an enlarged detail showing a forming block in side elevation, and Fig. detail of a portion of a bufling or polishing member. I V

For convenience of illustration the invention is-shown in a suitable form for use in buffing or polishing parabolic reflectors but it will be understood that other arrangements of parts may be made to adapt the same for use in buffing or polishing other articles having concave surfaces. As shown, a suitable base frame or standard 1 is provided with bearings 2 for a shaft 3 upon which is secured a pulley 4C for driving the shaft. Ar second pulleyl 5 of larger diameter is also secured'upon t e shaft 3 and frame membersti are mounted at each side of said pulley upon the shaft and supported attheir forward ends upon a pin 7 carried by a post 8 and projecting through a longitudinal further object is to secure an even pressure at all points of the buffer against the" 5 is a perspective face 18 of the slot 9 in extension -members l0 adjustably secured to the outer sides of the frame members by bolts 11 passing through slots in the extension members.

A forming guide block 12 is pivotally supportedbetween the forward ends of the extension arms by studs 13 on the sides of the block engaging bearing openings in the arms and this block is adjustably held against turning by means of an arm 14 on the block extending rearwardly therefrom and provided with a rod 15 at its rear end which rod is screwthreaded and passed through a block 16 pivoted between the arms 10 with nuts 17 on the rod above and below the block.

The block 12 has an edge face 18, a portion of which is curved to accurately conform to the curve in longitudinal section of the particular reflector 19 which it is desired to bud or polish. The reflector may be held in any suitable manner to be engaged by the buffing member hereinafter described, but it is preferably supported, as shown, by a suitable cap or socket member 20 on the end of a shaft 21 which is sup ported and rotated in any suitable manner, not shown. In use, the block 12 is held within the reflector and adjusted by means of the arm 14 until that portion of its lower face 18 which is adjacent to the surface of the reflector, is exactly parallel therewith. This edge face 18 of the block serves as a track for a series of rollers 22 which are,

spaced apart and held in parallelism by sprocket chains 23, the pivot pins of which chains are small shafts or rods 2t each extending through the links of one chain, through the adjacent roll, forming an axle therefor, and through the links of the chain at the opposite side. The rolls are of slightly greater length than the width of the block so that the chains travel adjacent to each side of the block where they are engaged by a pair of sprocket wheels 25 mounted on a shaft 26 located in the center from which is struck the line of the semicircular forward end of the block. The roller chain comprising the two sprocket chains and rollers, is thus held in place upon the block and guided around its forward end by said wheels, and as said chain is of just suflicient length to loosely encircle the block, it will travel freely upon the edge 110 face thereof.

An endless bufling or polishing belt 27 of suitable construction is passed over the pulley 5 and over the outer end of the forming block 12 against the roller chain thereon. The rolls 22 thus form a rolling support for the belt upon the block and eliminate friction, the belt being of substantially the same width as the block to engage the rolls between the sprocket chains. The path of travel of that portion of the belt which is adapted to engage the surface to be polished is'thus determined by the shape of the edge face of the block, as the belt is drawn tight to force it into firm contact with the chain which is-interposed between it and said face.

By swinging the block upon its pivot 13, it may be.adjusted to the surface to be polished and if it is desired to polish a surface having a widely different curve, a block of the proper outline. may be .substituted. In operation, the belt is positioned in the longitudinal vertical plane of the axis of the reflector so that it will travel in a plane at right angles to the plane of rotation of the reflector and thus travel across the surface to be polished in a direction longitudinally of the reflector. The semi-circular forward end of the block causes the belt to travel in a semi-circular path where it engages the inner end or bottomof the-concave surface of the reflector, the horizontal plane of the axial cen er of said end being. accurately positioned in the horizontal plane ofthe longitudinal axis of' the reflector and its carrying shaft. If found desirable, asmall gage the belt '27 and guide the same adjacent to the upper side and forward end of the forming block. This idler may be adjusted to tighten the belt and the arms 10 may be adjusted upon the frame members 6 for the same purpose by loosening the bolts 11.

As shown, the bufling or polishing belt is preferably formed of one or more thicknesses of belting 30 formed of leather or other suitable material to the outer face of ing or polishing surface. ishin beltis thus secured and the upstanding abric strips are adapted to hold an abrading substance.

Obviously changes. may be made in the construction and arrangement of parts without departing from the spirit of my invenidler pulley 28 carried by an adjustable yoke 29on the arms 10, may be providedto en- A flexible pol-' tion and I do not therefore limit myself to the construction shown.

Having thus fully described my invention what I claim is 1. In a machine of the character de scribed, the combination of an endless taut tion reducing devices interposed between said belt and said forming member.

3. In a machine of the character described, the combination of an abrasive belt, a forming member havlng a surface curved to conform to the surface of Work, an endless chain having a series of rollers adapted to travel over said surface of the forming member between the belt and said forming member, and means for drivin the belt.

4. In a machine of the c aracter described, the combination of an endless abrasive belt, a driving pulley for said belt, a pivoted forming member movable to and from said pulley and having a surface curved to correspond with the curvature of the surface of work and over which curved surface the belt is adapted to pass, and means for adjustably supporting said form'- ing member to increase and decrease the abrading area of said belt relative to a piece of work.-

5. In a machine of the character described, the combination of an endless flexible abrasive belt, a driving pulley for said belt, a block having a formed surface over which said belt is adapted to pass, a chain provided with a series of rollers surrounding said block and passing between said belt and said formed surface.

In a machine of the character. described, the combination of an abrasive belt, 'a driving pulley for said belt, a pivoted forming block having a curved edge surface conforming to the curvature of the surface of work, means for adjustably supporting said block at a distance from said pulley to guide said belt in a curved path throughout the portion of its travel in which it is adaptor. polishing the combination of an rmaeaa 333 edge surface formed throughout a portion of its length to conform to the curvature of a surface to be polished or bufi'ed, means for pivotally supporting said block at a distance from said pulley, a chain surrounfiing saicl block and having a series of rollers running upon saicl edge surface thereof with the belt in contact with said rollers opposite the said portion of the curved edge surface of the block, and means for acljusting saia 10 block upon the pivotal support.

In testimony whereof I aflix my signature in presence of two witnesses,

HARRY J. WEBB.

Witness-es:

ANNA M. Dorm, Cues. W. STAUFFIGER. 

